The disclosure concerns a sealing element for sealing a high-pressure side from a low-pressure side at a rotating shaft, in particular in a pump, with a supporting ring which is to be arranged on a stator surrounding the shaft and from which a first annular membrane protrudes facing in the direction toward the shaft.
In particular in pumps, higher requirements are imposed on sealing elements for sealing rotating shafts compared with conventional shaft seals. The reason is mainly that a high pressure predominating on the high-pressure side can change greatly relative to the low pressure on the opposite side of the sealing element, and the pressure relationships of high pressure to low pressure can even sometimes reverse. When a low pressure occurs in a chamber which must otherwise be sealed for high pressure, in conventional shaft seals the sealing membrane lifts away from the shaft. As a result, in particular air can penetrate into the system to be sealed. Under a high positive pressure in the system, the sealing membrane with its sealing edge can be pressed so strongly against the shaft that increased friction losses and increased wear can result.
The consequence may be leaks and a shorter service life of the sealing element with its tribological system.
However, dynamic shaft seals for sealing rotating shafts which, in particular on a change of pressure relationship or on pressure fall, achieve a high sealing effect but only generate low friction losses and which are also formed compactly, are not known.